Adjustable pulley



Sept 23, 1952 G. o. TURNBULL 2,611,278

ADJUSTABLE 'PULLEY I Filed Dec. 26. 1947 2 SHEETSSHEET 1 INVENTOR. 676/2 (7. fizz nZuz/Z P 1952 G. o. TURNBULL 2,611,278

ADJUSTABLE PULLEY Filed Dec. 26, 1947 2 SHEETS-SHEET 2 INVENTOR. 616a@72072154/1 Po... QO- ;;5/3 33 fiatenteci Sept. 23, 1952 ADJUSTABLEPULtE'Y' Glen 0. Turnbull, Rock Island, 111., assignor' td 4 tion of NewJersey 7 International Harvesterflompany, a corpora- ApplicationDecember 26, 1947, serial No. 793,931

1 Claim.

This invention relates to a newand improved adjustable pulley. l

A principal object of this invention is to provide a pulley especiallyadapted for V-belts and having means incorporated therein for adjustablespacing of the walls of the pulley to effect variable shaft drivingspeeds by changing the pitch v diameter-of the belt.

"An" important object ofthis' invention is the provision ofa two-partadjustable V-beltpulley having means therein fora'djustably spacing thetwo parts and separate means for imparting rota- 'tive drivefrom-one-partto the-other part of the pulley.

Still? another important object of this invention is to provide asimpleiadjustable V-belt pulley employing a minimum ot working partswith maximum drive strength-in any of the infinite openings of thepulley. I V

Other and further-important objects of'this invention will becomeapparent from the disclosures in the following specification andaccompanying drawings in which:

Fig. 1 is a vertical sectional view taken through the adjustable pulleyof this invention.

Fig. 2 is a side elevational view of the pulley as viewed from line 2-2of Fig. 1.

Fig. 3 is a sectional view taken on the line 3-3 of Fig. 1.

As shown in the drawings, the reference numeral I indicates generally ashaft on which is mounted the adjustable pulley of this invention. Oneend of the shaft I9 is provided with a collar II held in fixed positionby means of a threaded bolt I2 having an enlarged head [3 engaging alock washer I4 which bears directly on the collar I I. The bolt I2 hasthreaded engagement with the shaft Ill.

The pulley is provided with an internal hub I5 mounted on the shaft I9and held in fixed rotative relationship with the shaft by means of a keyI6 extending within the opposed aligned key ways I! and I8 in the shaftI0 and the hub I5. One-half section l9 of the pulley is integrallyassociated with the hub l5. A section complements the section I9 andcompletes the V-belt pulley. The section 29 of the pulley has anexternal hub 2| slidable over the hub l5 of the pulley section I9.

As best shown in Fig. 3 the hub I5 is substantially triangular in shapeand has three apices 22, 23, and 24. The external sleeve hub 2I of thepulley section 29 is also substantially triangular in its internal shapeand has three internal spices 25, 26, and 21. Rotational drive from theshaft I9 is thustran'smitted outwardly to the hub [5 through the keyIISand from the apicesof "the hub I5 to the similar apices of thesleevehub 2I'." The pulley sections I9 and 20 thus'mo've' as a unit,and'complete' drive is accomplished through the triangular" sleeve hub2| telescoped over the triangular hub I5. Set or looking screws 28 and29 threadedly engage bosses 30 and 3| in the sleeve hub 2|. The screw 28is adapted to passthrough. the boss 39 and contact the. apex 24 of thetriangular hub l5. Similarly, the screw 29 passes through the boss 3|and engages the apex; 23 of the triangular hub I5. When thesetwoset-screws 2 8- andf29 are turned up tightly, relative movementbetween the triangular hubs I5 and H is not permitted. I

The pulley sections I9 and 20 as shown in Fig.

l 1 abut each other at their hubends. One of the prime objects of thisinvention is the lateraladjustability of one section ofthe pulley withrespect to the other section of the pulley to effect variable speeddrive by causing the belt to ride in the pulley either at a positionnear the outer periphery or at some position between the outer peripheryand the hub by proper spacing of the pulley sections. The pulleysections or parts I9 and 20 are held together by two bolts 32 and 33.The bolt 32 passes through aligned apertures 34 and 35 in the pulleysections I9 and 20 respectively. The bolt head 36 is positioned within asquare recess 31 in the outer surface of the pulley section I9. Thesquare head 36 engages a shoulder 38 at the outer end of the passage 34,thus holding the bolt 32 in position. A nut 39 engages the outer end ofthe shank of the bolt 32 and is drawn up against the outer wall 49 ofthe pulley section 29. A second nut 41 threadedly engages the bolt 32and is drawn up against the nut 39, looking it in fixed position. Aspreviously stated as shown in Fig. 1, the pulley sections are adjustedfor the tightest belt position with the inner surface 42 of the pulleysection 20 abutting theinner surface 43 of the pulley section [9.Similarly to the structure adjacent the bolt 32 the bolt 33 passesthrough aligned passages or apertures 44 and 45 and is equipped with asquare head 46 positioned within a square recess 41. The head engages ashoulder 48 and a pair of nuts 49 and 50'lock the pulley sections infixed spaced position. When it is desired to space the section 29 awayfrom the section I9, the nuts 4I and 53 are withdrawn from theirabutting positions with respect to the nuts 39 and 49 respectively. Thenext step is to withdraw the nuts .39 and 49 from their positionengaging the outer face 40 of the pulley section 20. The set screws 28and 29 are loosened and the pulley section 20 may now be shiftedlaterally with respect to the pulley section I9 a distance determined bythe withdrawn position of the nuts 39 and 49.

When the desired spacing of the pulley sections is obtained the setscrews 28 and 29 are retightened and the lock nuts 4| and 50 are drawnup against the nuts 39 and 49. The action of a V- belt within the pulleytends to spread the sections l9 and 20 so that there is a minimum oftendency for the sections l9 and 20 to travel toward each other. Such atendency is further overcome by the set screws 28 and '29. which,although primarily compensate for relative rota tional movement betweenthe hubs l5 and 2|, also limit relative lateral shifting of the, hubs l5and 2|. The pulley spacing bolts 32 and 33 do not receive any of thetorsional driving strain and thus are always readily adjustable.

The pulley of this invention is adapted for use invariable speedarrangements wherein it. is de- ..sired to change they pitch diameter ofthe,- pulley.

As a rule two such adjustable pulleys are used at opposite ends of aV-belt whereby upon adiustment of both pulleys simultaneously andoppositely the. length of the belt; remains constant but the drivingratio between the two pulleys is changed.

. I am aware that many details. of construction may be varied over awide range without departing from the principles disclosed herein, and Itherefore donot propose limiting the patent granted hereon otherwisethan as necessitated by the appended claim.

What is claimed is:

An adjustable V-belt pulley comprising adjacent pulley side sections,each oi; said side sections having integral hubs, said hubs both,extending laterally in the same direction, the first of said hubs havinga shaft engaging opening and an external substantially triangular shape.the second of said hubs having an internal opening corresponding inshape to the external substantially triangular shape of the first hub,said second hub positioned over and around said first hub and permittinglateral sliding movement of the. pulley side sections with respect toeach other and causing concurrent rotation of the pulley side sections,bolt means passing through the adjacent pulley side sections spacedoutwardly of said hubs for adjustably joining said adjacent pulley sidesections in any desired lateral spacing and set screws positioned insaid second hub and passing therethrough to abutting engagement with thefirst hub whereby all relative rotative motion between the two hubs iseliminated.

. GLEN O. TURNBULL.

REFERENCES CITED.

' The following references areof record in the file of this patent:

UNITED. STATES PATENTS

